Google Cardboard is an 'invaluable opportunity' for VR devs

The virtual reality market is ever growing, with Oculus and HTC now releasing their VR products – soon to be followed by Sony. No reasonable person doubts their quality and what a unique opportunity those platforms represent. However, with all the hype, we're forgetting VR’s much quieter cousin – The Google Cardboard, which Google is gambling will capture an audience that high-end VR can only wish for.

Now let’s be clear, I love high-end VR and I know it will capture a wide audience of tech lovers, hardcore gamers and plenty of other groups. But the Google Cardboard offers unique opportunities and challenges for developers and consumers alike – and here’s why:

Opportunities

VisibilityHigh-end VR is impressive and has great visibility, but that pales in comparison with the potential userbase of low-end VR devices such as the Cardboard. The unique opportunity to capitalise on a new market is even wider.

We know that the mobile market for game development is now virtually impenetrable, with over 500 apps released on Apple's App Store every day. The problem with mobile is visibility and saturation. Because of this low visibility for new apps, unless you have a massive marketing budget or a large dose of luck, you’ll be more than likely left behind.

The Cardboard gives your application a fair chance to attract a userbase by having much less competition, and it reinvigorates the mobile market for those who wouldn't normally have stood a chance. Why not be part of that?

PrototypingCardboard offers the unique opportunity to be able to prototype a potential game idea without having to shell out the mega bucks for a new PC and headset. Standards haven't been defined yet and many game ideas haven't been tried in VR, so there's no guarantee that an idea will actually work as you intended.

Using Cardboard as a prototyping tool, you can gain an understanding of the potential drawbacks to your ideas and amend your designs based on that feedback before committing to purchasing a high-end headset.

Challenges

Device Architecture & SupportWith the wide range of devices, there comes a wide range of problems. Some manufacturers' gyroscopes randomly skipping, or seeing graphic artifacts on certain devices are amongst some of the challenges we've experienced.

Quite simply though, with Cardboard still being an emerging market, there's the time to find these problems and mistakes now before the real test of when Cardboard is launched as an official product. For the most part, these problems are fixable – and if the worst comes to the worst, you can exclude certain devices from accessing your Cardboard product.

The devices themselves are also being asked to do something against normal expectations. Apps and games traditionally are designed to be efficient with battery use and heat, and are resistant to the idea of having their hardware pushed.

Performance throttling is a usual occurrence in mobile games which usually has a minimal impact on the end user’s experience. With VR, however, throttling has the potential to cause motion sickness if the application can’t stay at 60fps, so ensuring your application can deal with throttled hardware is an important consideration for Cardboard experiences.

Being OptimalHigh-end VR expects you to buy a high-end PC to allow the headset to function sufficiently.

There is, however, no expectation that users should buy a new phone to run a Cardboard experience – at least not yet. You should factor in what percentage of that potential mobile market you're willing to target, and develop your game with optimisation in mind.

Being efficient on the GPU is especially important. My best tips for this are:

A low batch/draw call count is vital. Use texture atlasing, shared materials and static/ dynamic batching to help with this.

Consider overdraw and fill rate. Less transparency, alpha testing and the smaller the target render texture, the better.

Benchmark and benchmark often.

My suggestion is, if you're thinking of creating a VR product, do consider if a version could work in Google Cardboard. You may have to compromise parts of your grand original idea you had in mind with high-end VR, but for the most part, many restrictions can be cleverly worked around.

If you can then execute the implementation of that game and get a well-performing Cardboard game out of it, you'll have a market opportunity that could be invaluable.

Lukas is the lead developer at Opposable Group and has worked on a number of Oculus and Samsung Gear projects. He is currently also working on an unannounced Cardboard project. You can follow him on Twitter via @LukasRoper.

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